SECONDARY BATTERY OF IMPROVED SAFETY EMPLOYING ELECTRODE ASSEMBLY COVERED WITH SEPARATOR FILM

摘要

A lithium ion polymer secondary battery including an electrode assembly surrounded with a separator film is provided to prevent an internal short when the electrode assembly moves upon dropping of the battery while not adversely affecting the electrolyte used in the battery. A lithium ion polymer secondary battery comprises an electrode assembly(300) including a separator having an adhesive layer coated on both surfaces thereof, a cathode and an anode attached to both surfaces of the separator with the adhesive layer, and a lithium electrolyte, wherein the outer surface of the electrode assembly is surrounded with a film(600) coated with an adhesive layer formed of the same fluoropolymer as the separator along the direction toward the electrode terminals(400,410) of the electrode assembly.